Add radio now-playing metadata polling and readonly props

docs/item-schema.md

@@ -65,6 +65,8 @@
   "mediaVolume": 50,
   "mediaEffect": "off",
   "mediaEffectValue": 50,
+  "stationName": "",
+  "nowPlaying": "",
   "facing": 0,
   "emitRange": 10
 }
@@ -77,6 +79,9 @@
 - `mediaChannel`: one of `stereo | mono | left | right`, default `stereo`.
 - `mediaEffect`: one of `reverb | echo | flanger | high_pass | low_pass | off`, default `off`.
 - `mediaEffectValue`: number, range `0-100`, precision `0.1`.
+- UI visibility: `mediaEffectValue` is shown only when `mediaEffect != off` (`visibleWhen: {"mediaEffect": "!off"}`).
+- `stationName`: server-managed station label derived from ICY metadata when available.
+- `nowPlaying`: server-managed stream title derived from ICY metadata when available.
 - `facing`: number, range `0-360`, step `1` (used when `directional=true`).
 - UI visibility: `facing` is shown only when `directional=true` (`visibleWhen` metadata).
 - `emitRange`: integer, range `5-20`, default `10`.

docs/item-types.md

@@ -25,6 +25,8 @@ This is behavior-focused documentation for item types and their defaults.
   - `mediaVolume=50`
   - `mediaEffect="off"`
   - `mediaEffectValue=50`
+  - `stationName=""` (server-managed, read-only)
+  - `nowPlaying=""` (server-managed, read-only)
   - `facing=0`
   - `emitRange=10`
 - Global:
@@ -42,8 +44,10 @@ This is behavior-focused documentation for item types and their defaults.
 - `mediaVolume`: integer `0..100`
 - `mediaEffect`: `reverb | echo | flanger | high_pass | low_pass | off`
 - `mediaEffectValue`: number `0..100` with `0.1` precision
+  - Visible only when `mediaEffect != off` (`visibleWhen: {"mediaEffect": "!off"}`)
 - `facing`: number `0..360` with step `1`
 - `emitRange`: integer `5..20`
+- `stationName` / `nowPlaying`: server-fetched metadata fields; not editable by clients.
 
 ## `dice`
 

docs/protocol-notes.md

@@ -50,6 +50,7 @@ This is a behavior guide for packet semantics beyond raw schemas.
 - `item_use_sound` contains absolute item world coordinates (`x`, `y`) and sound path.
   - For carried items, source coordinates resolve to the carrier's current position.
 - `teleport_complete` contains absolute player world coordinates (`x`, `y`) at teleport landing.
+- Radio metadata (`params.stationName`, `params.nowPlaying`) is server-managed and delivered through normal `item_upsert` updates.
 - `item_piano_note` contains:
   - `itemId`, `senderId`, `keyId`, `midi`, `on`
   - resolved `instrument`, `voiceMode`, `octave`, `attack`, `decay`, `release`, `brightness`, `emitRange`
@@ -81,6 +82,7 @@ This is a behavior guide for packet semantics beyond raw schemas.
   - `itemTypes[].globalProperties`: non-editable global values (`useSound`, `emitSound`, `useCooldownMs`, `emitRange`, `directional`, `emitSoundSpeed`, `emitSoundTempo`)
 - Client item UI requires this metadata from the server; there is no fallback item definition map.
 - Client property help/type rendering is metadata-driven; it does not infer fallback types/tooltips from hardcoded key heuristics.
+- `visibleWhen` supports equality checks and string negation via `!` prefix (example: `{"mediaEffect": "!off"}`).
 
 ## Validation Boundaries